Slides
Lesson slides
Slides for the lesson
Open resourceLesson 04
Building Circuits
Construct and compare series and parallel circuits using correct symbols, meter placement, and circuit rules.
Objectives
Lesson outcomes
- Draw and interpret simple circuit diagrams using standard symbols for common components, including diodes and LEDs.
- Build series and parallel circuits correctly and place ammeters and voltmeters in the correct positions.
- Compare how current and potential difference behave in series and parallel circuits, including the junction rule.
- Calculate the combined e.m.f. of cells in series and explain why lamps in domestic lighting circuits are connected in parallel.
Syllabus
CIE 0625 syllabus points
9 linked
- 4.3.1.1 Draw and interpret circuit diagrams containing cells, batteries, power supplies, generators, potential dividers, switches, resistors (fixed and variable), heaters, thermistors (NTC only), light- dependent resistors (LDRs), lamps, motors, bells, ammeters, voltmeters, magnetising coils, transformers, fuses and relays and know how these components behave in the circuit
- 4.3.1.2 Draw and interpret circuit diagrams containing diodes and light-emitting diodes (LEDs) and know how these components behave in the circuit
- 4.3.2.1 Know that the current at every point in a series circuit is the same
- 4.3.2.2 Know how to construct and use series and parallel circuits
- 4.3.2.3 Calculate the combined e.m.f. of several sources in series
- 4.3.2.5 State that, for a parallel circuit, the current from the source is larger than the current in each branch
- 4.3.2.7 State the advantages of connecting lamps in parallel in a lighting circuit
- 4.3.2.8 Recall and use in calculations, the fact that: (a) the sum of the currents entering a junction in a parallel circuit is equal to the sum of the currents that leave the junction (b) the total p.d. across the components in a series circuit is equal to the sum of the individual p.d.s across each component (c) the p.d. across an arrangement of parallel resistances is the same as the p.d. across one branch in the arrangement of the parallel resistances
- 4.3.2.9 Explain that the sum of the currents into a junction is the same as the sum of the currents out of the junction
Lesson Notes
Student guidance and lesson notes
Overview
This lesson should feel practical and precise. You need enough fluency with circuit symbols, layout, and meter placement that you can build, test, and discuss a circuit without treating the diagram and the real equipment as separate tasks.
What You Need to Know
- Revisit the standard symbols for cells, switches, lamps, resistors, variable resistors, meters, diodes, and LEDs before any practical work starts.
- Model how to translate a circuit diagram into a physical setup, keeping polarity and meter placement visible.
- Compare series and parallel arrangements using current and p.d. ideas from the previous lesson.
- Show how cells in series combine to give a larger total e.m.f.
- Use lighting circuits as the key real-world example for why parallel branches are often preferred.
How to Work Through It
- Start with a symbol-matching recall task and a quick correction of one deliberately flawed circuit diagram.
- Model a simple series circuit from diagram to bench, then repeat with a parallel circuit and ask you to identify what changes.
- Build tasks around measuring current and p.d. in different positions, including one example with more than one cell in series.
- Finish with a comparison between a series lighting circuit and a parallel lighting circuit, focusing on brightness, independence, and reliability.
Check Your Understanding
- Check whether you can choose the correct diagram for a circuit containing an LED and explain the component orientation.
- Use a meter-placement hinge question where you must decide where to put an ammeter and a voltmeter for the same circuit.
- Give a short series-parallel comparison and ask which circuit would be better for household lighting, with a reason.
Common Mistakes
- Confusing a physical layout with the electrical arrangement. Keep tracing the path of charge through the diagram and the real circuit side by side.
- Some think current is “used up” by the first lamp in a series circuit. Revisit the rule that the current is the same at every point in a series circuit.
- LED orientation and meter placement are common practical errors. Model these explicitly before you build independently.
Next Steps
- Set a short diagram-drawing task so the symbol knowledge stays secure between lessons.
- Carry forward the circuit layouts and meter methods into the resistance lesson, where accurate measurement matters.
Lesson Resources
Materials for this lesson
Use these videos, slide decks, documents, or links to work through the lesson.